1. Field of the Invention
The present invention relates to a rechargeable battery and a battery module, and more particularly, to the rechargeable battery and the battery module having an improved structure for supporting an electrode assembly.
2. Description of the Related Art
In contrast to a primary battery incapable of charging, the rechargeable battery is a battery capable of charging and discharging.
Rechargeable batteries of a small capacity may be used for small portable electronic equipment such as cellular phones, notebook computers, camcorders and the like. Rechargeable batteries of a large capacity, wherein multiple cells are connected in the form of a pack or module, may be used as a power supply for driving motors, such as those used in hybrid electric vehicles, and the like.
The rechargeable battery (also generally referred to as a unit battery) can be manufactured in various forms, such as a pouched type, a cylindrical type, or an angular type.
Among others, the pouched type of the battery is widely used for slim and light-weight portable electronic equipment due to its relatively modifiable and light-weight properties.
Thus, in contrast to the casing of the cylindrical or the angular type of the battery molded by a thick metal material, the casing of the pouched type of the unit battery has a structure capable of bending freely since both surfaces of a thin metal film are attached to an insulating film. In addition, the inside of the casing is provided with a spatial area capable of holding the electrode assembly. Also, a sealing surface heat-fused along the periphery of the spatial area is provided.
For the conventional pouched type of the unit battery, it is very difficult to apply a separate structure for improving a heat radiating property to the casing, since the casing itself forming an outside of the battery is made of a flexible material that is typically weak in strength.
Thus, conventionally, the heat dissipating body is separately manufactured of a hard material and is used as the structure for receiving and holding the pouch.
However, the disadvantage of the conventional heat dissipating body is that it cannot apply pressure uniformly to the entire pouch. A planar type of heat dissipating body cannot uniformly apply a pressure to the entire electrode assembly since the electrode assembly inserted into the pouch may have a dumbbell-shaped sectional structure.